并发登录人数控制--Shiro系列(二)

叁歲伎倆 2022-09-21 14:28 193阅读 0赞

为了安全起见，同一个账号理应同时只能在一台设备上登录，后面登录的踢出前面登录的。用Shiro可以轻松实现此功能。

shiro中sessionManager是专门作会话管理的，而sessinManager将会话保存在sessionDAO中，如果不给sessionManager注入

sessionDAO，会话将是瞬时状态，没有被保存起来，从sessionManager里取session,是取不到的。

此例中sessionDAO注入了Ehcache缓存，会话被保存在Ehcache中，不知Ehcache为何物的，请自行查阅资料。

完整demo下载：http://download.csdn.net/detail/qq\_33556185/9555720

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shiro.xml

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
    	xmlns:mvc="http://www.springframework.org/schema/mvc"
    	xsi:schemaLocation="http://www.springframework.org/schema/beans   
        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd   
        http://www.springframework.org/schema/tx   
        http://www.springframework.org/schema/tx/spring-tx-4.2.xsd  
        http://www.springframework.org/schema/context  
        http://www.springframework.org/schema/context/spring-context-4.2.xsd  
        http://www.springframework.org/schema/mvc  
        http://www.springframework.org/schema/mvc/spring-mvc-4.2.xsd">
         
    <bean id="sessionManager" class="org.apache.shiro.web.session.mgt.DefaultWebSessionManager">  
            <property name="globalSessionTimeout" value="1800000"/>  
            <property name="deleteInvalidSessions" value="true"/>  
            <property name="sessionDAO" ref="sessionDAO"/>  
            <property name="sessionIdCookieEnabled" value="true"/>  
            <property name="sessionIdCookie" ref="sessionIdCookie"/>  
            <property name="sessionValidationSchedulerEnabled" value="true"/>
            <property name="sessionValidationScheduler" ref="sessionValidationScheduler"/>
             <property name="cacheManager" ref="shiroEhcacheManager"/>
    </bean>  
    	     
        <bean id="sessionDAO" class="org.apache.shiro.session.mgt.eis.EnterpriseCacheSessionDAO">  
            <property name="sessionIdGenerator" ref="sessionIdGenerator"/>  
            <property name="activeSessionsCacheName" value="shiro-activeSessionCache"/>
        </bean> 
    	  
      <bean id="shiroEhcacheManager" class="org.apache.shiro.cache.ehcache.EhCacheManager">  
      <property name="cacheManagerConfigFile" value="classpath:ehcache.xml" />  
      </bean>
    <bean id="sessionIdCookie" class="org.apache.shiro.web.servlet.SimpleCookie">  
            <constructor-arg value="sid"/>
            <property name="httpOnly" value="true"/>
            <property name="maxAge" value="-1"/> 
    </bean> 
     
     <bean id="sessionIdGenerator" class="org.apache.shiro.session.mgt.eis.JavaUuidSessionIdGenerator"></bean>
    <bean id="kickoutSessionControlFilter"  class="com.core.shiro.KickoutSessionControlFilter">  
        <property name="sessionManager" ref="sessionManager"/>  
        <property name="cacheManager" ref="shiroEhcacheManager"/>
        <property name="kickoutAfter" value="false"/>  
        <property name="maxSession" value="1"/>  
        <property name="kickoutUrl" value="/toLogin?kickout=1"/>  
    </bean> 
          <bean id="logout" class="org.apache.shiro.web.filter.authc.LogoutFilter">
            <property name="redirectUrl" value="/toLogin" />
           </bean> 
              
        <bean id="sessionValidationScheduler" class="org.apache.shiro.session.mgt.ExecutorServiceSessionValidationScheduler ">
            <property name="interval" value="1800000"/>
            <property name="sessionManager" ref="sessionManager"/>
        </bean>
    	   
        <bean id="shiroFilter" class="org.apache.shiro.spring.web.ShiroFilterFactoryBean">  
              
            <property name="securityManager" ref="securityManager" />  
              
            <property name="loginUrl" value="/toLogin" />  
              
            <property name="unauthorizedUrl" value="/unauthorizedUrl.jsp" />  
           
              
             <property name="filters">  
             <map>  
                 <entry key="kickout" value-ref="kickoutSessionControlFilter"/>  
             </map>  
         </property> 
            <property name="filterChainDefinitions">  
                <value>  
                	/loginin=kickout,anon
                	 /logout = logout
                	/toLogin=anon
                	/css/**=anon 
                    /html/**=anon 
                    /images/**=anon
                    /js/**=anon 
                    /upload/**=anon 
                    
                    /userList=kickout,authc,perms[/userList]
                    /toRegister=kickout,authc,perms[/toRegister]
                    /toDeleteUser=kickout,authc,perms[/toDeleteUser]
                    /** = kickout,authc
                 </value>  
            </property>  
        </bean>  
      
          
        <bean id="securityManager" class="org.apache.shiro.web.mgt.DefaultWebSecurityManager">  
            <property name="realm" ref="myRealm" />  
             <property name="sessionManager" ref="sessionManager"/>
             <property name="cacheManager" ref="shiroEhcacheManager"/>
        </bean>  
         
        <bean id="myRealm" class="com.core.shiro.CustomRealm" />  
        
        <bean id="lifecycleBeanPostProcessor" class="org.apache.shiro.spring.LifecycleBeanPostProcessor" />
        
        <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">  
    	   <property name="prefix" value="/"/>  
    	   <property name="suffix" value=".jsp"></property>  
    	</bean>
    </beans>

ehcache.xml

<?xml version="1.0" encoding="UTF-8"?>  
    <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
        xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd"  
        updateCheck="false" maxBytesLocalDisk="20G" maxBytesLocalOffHeap="50M">
          
        <diskStore path="java.io.tmpdir"/> 
        <defaultCache eternal="false"   
            maxElementsInMemory="10000"  
            overflowToDisk="false"   
            timeToIdleSeconds="0"  
            timeToLiveSeconds="0"   
            memoryStoreEvictionPolicy="LFU" />  
       
        <cache name="myCache"  eternal="false"   
            maxElementsInMemory="10000"  
            overflowToDisk="false"   
            timeToIdleSeconds="0"  
            timeToLiveSeconds="0"   
            memoryStoreEvictionPolicy="LFU" />  
        <cache name="shiro-activeSessionCache" eternal="false"
              maxElementsInMemory="10000"  
              overflowToDisk="true"
              timeToIdleSeconds="0"
              timeToLiveSeconds="0"/>
    </ehcache>

KickoutSessionControlFilter：

package com.core.shiro;
    
    import java.io.Serializable;
    import java.util.Deque;
    import java.util.LinkedList;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    import org.apache.shiro.cache.Cache;
    import org.apache.shiro.cache.CacheManager;
    import org.apache.shiro.session.Session;
    import org.apache.shiro.session.mgt.DefaultSessionKey;
    import org.apache.shiro.session.mgt.SessionManager;
    import org.apache.shiro.subject.Subject;
    import org.apache.shiro.web.filter.AccessControlFilter;
    import org.apache.shiro.web.util.WebUtils;
    public class KickoutSessionControlFilter  extends AccessControlFilter{
    	private String kickoutUrl; //踢出后到的地址
        private boolean kickoutAfter; //踢出之前登录的/之后登录的用户 默认踢出之前登录的用户
        private int maxSession; //同一个帐号最大会话数 默认1
        private SessionManager sessionManager;
        private Cache<String, Deque<Serializable>> cache;
    
        public void setKickoutUrl(String kickoutUrl) {
            this.kickoutUrl = kickoutUrl;
        }
    
        public void setKickoutAfter(boolean kickoutAfter) {
            this.kickoutAfter = kickoutAfter;
        }
    
        public void setMaxSession(int maxSession) {
            this.maxSession = maxSession;
        }
    
        public void setSessionManager(SessionManager sessionManager) {
            this.sessionManager = sessionManager;
        }
    
        public void setCacheManager(CacheManager cacheManager) {
            this.cache = cacheManager.getCache("shiro-activeSessionCache");
        }
         /**
          * 是否允许访问，返回true表示允许
          */
        @Override
        protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) throws Exception {
        	return false;
        }
        /**
         * 表示访问拒绝时是否自己处理，如果返回true表示自己不处理且继续拦截器链执行，返回false表示自己已经处理了（比如重定向到另一个页面）。
         */
        @Override
        protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {
            Subject subject = getSubject(request, response);
            if(!subject.isAuthenticated() && !subject.isRemembered()) {
                //如果没有登录，直接进行之后的流程
                return true;
            }
    
            Session session = subject.getSession();
            String username = (String) subject.getPrincipal();
            Serializable sessionId = session.getId();
    
            // 初始化用户的队列放到缓存里
            Deque<Serializable> deque = cache.get(username);
            if(deque == null) {
                deque = new LinkedList<Serializable>();
                cache.put(username, deque);
            }
    
            //如果队列里没有此sessionId，且用户没有被踢出；放入队列
            if(!deque.contains(sessionId) && session.getAttribute("kickout") == null) {
                deque.push(sessionId);
            }
    
            //如果队列里的sessionId数超出最大会话数，开始踢人
            while(deque.size() > maxSession) {
                Serializable kickoutSessionId = null;
                if(kickoutAfter) { //如果踢出后者
                	kickoutSessionId=deque.getFirst();
                    kickoutSessionId = deque.removeFirst();
                } else { //否则踢出前者
                    kickoutSessionId = deque.removeLast();
                }
                try {
                	Session kickoutSession = sessionManager.getSession(new DefaultSessionKey(kickoutSessionId));
                    if(kickoutSession != null) {
                        //设置会话的kickout属性表示踢出了
                        kickoutSession.setAttribute("kickout", true);
                    }
                } catch (Exception e) {//ignore exception
                	e.printStackTrace();
                }
            }
    
            //如果被踢出了，直接退出，重定向到踢出后的地址
            if (session.getAttribute("kickout") != null) {
                //会话被踢出了
                try {
                    subject.logout();
                } catch (Exception e) { 
                }
                WebUtils.issueRedirect(request, response, kickoutUrl);
                return false;
            }
            return true;
        }
    }

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